There has been a rapid growth in innovations towards making space travel more plausible for future colonists. Space agencies like SpaceX led by CEO Elon Musk propounded that it will send humans to Mars by 2022 while other space agencies like NASA have their own plans for the future. But before the mission to humans to Mars can be achieved, there is a major obstacle that requires immediate solution. It would take humans nine months to travel from Earth to Mars which means that travelers will be exposed to harmful radiation for a greater duration which can lead to cancer. Scientists have developed a set of drugs that can combat the radiation exposure on the humans.
Earth has a charged magnetic field that protects it from harmful space radiation and that is what aids the astronauts during their stay on ISS. But traveling to Mars comes with its own challenges such as the spacecraft will leave the magnetic shield of Earth during its journey that will expose it to high levels of radiation causing harm to the body of the astronauts and space travelers. This can cause radiation sickness or worst, an escalated risk of developing cancer and other degenerative diseases. As per the statistics, astronauts are exposed to around 800 to 1,200 millisieverts (mSv) of radiation in his entire career. mSv is the scale used to gauge the level of radiation. It is estimated that a round trip to Mars would result in the exposure of up to 660 mSv which is almost near to the lower limit of radiation exposure by an astronaut in his entire career.
Thus, scientists are presently experimenting with drugs that can shield humans from such harmful levels of radiation. In one such attempt, Insilico Medicine, a medical firm which has a panel of international scientists plus researchers from American space agency, has developed radiation combating drugs. As per Dr. Alex Zhavoronkov, CEO of the company, the cost of what is called as one ‘Productive Life Year (PLY)’ of humans on Mars is likely to be more expensive compared to that on Earth. This makes it crucial for the scientists to find a way to maximize the PLYs spend on the red planet. It is more important to curb the effect of High Linear Energy Transfer (LET) radiation that the colonists will face on Mars. The firm has suggested the use of radioprotectors to prevent the astronauts and colonists from exposure to radiation. Radioprotectors are molecules that limit the exposure of radiation by protecting the body against the agents that could harm. Researchers have found a striking resemblance between DNA damage in aging and radiation exposure thus, it has suggested the use of anti-aging compounds that can combat radiation.
Zhavoronkov said that since Elon Musk has planned to send humans to Mars and built a colony, the radioresistance technology will enable protection from radiation and increase the time spent on the red planet. The firm is presently in talks with NASA which is interested in the idea of radioresistance. The firm is developing prospective drugs that will serve its purpose of combating radiation when the first set of colonists and astronauts liftoff towards a nine-month journey to the red planet.
How does this radioprotector work?
Zhavoronkov stated the working of the radioprotectors which consists of molecules mainly senoremediators, geroprotectors, and senolytics.
These molecules have the ability to slow down the process of aging or even reversing some of the processes. Metformin, Rapamycin are few of the known compounds that are presently in use in animals. Geroprotectors protects against radiation exposure but it has a number of side effects and that is why researchers are experimenting with other alternatives. For now, compounds like Withaferin A, riboside, nicotinamide have been effective in protecting against harmful radiation.
These are molecules that tend to reverse the cell back to its young age. Compounds like EGCG, NAC, and myricetin are classified as senoremediators. But there is an array of other molecules that can be used as alternatives.
These molecules kill full-senescent cells in the body where there is a small probability that some of the cells might turn cancerous. Senolytics can be used to kill and remove fully-senescent cells. The basic requirements for applying senolytics is that senoremediators are required to be applied first.