During extended microgravity flights, astronauts experience bone density loss. This is why there have been so few moon landing missions in space science history. A rapid decrease in bone density is considered life-threatening, and this is a major concern that space organizations are intended to overcome before sending humans to Mars.
Experiments on a group of courageous astronaut mice, on the other hand, have provided a huge boost to the objective of sending humans to Mars.
The mice were the first animals to return to Earth safely from space, pointing to a potential strategy for reducing bone density loss in astronauts during extended microgravity missions.
The mice were taken to the International Space Station (ISS) as part of a study, the findings of which were published in the journal npj Microgravity.
Half of the mice were placed in a capsule and returned to Earth halfway through the study, making it the “first ever live animal return of mice in US history.”
NASA praised the work, noting in an official statement that “rodents help NASA take the next step to Mars.”
Weightlessness is experienced by astronauts aboard the ISS because both the space station and its occupants are in freefall, giving the impression of “microgravity.”
How was the research carried out?
A SpaceX spaceship sent 40 mice to the International Space Station in 2017. To address the issue of microgravity exposure, researchers from the University of California, Los Angeles (UCLA) and the Forsyth Institute in Massachusetts created a therapy incorporating a supplement called neural epidermal growth factor-like 1 protein (Nell-1).
The mice were given either the Nell-1 protein or an inert saline solution by astronauts Peggy Whitson and Jack D Fischer on board the International Space Station. For comparison, another group of mice on the ground in Florida received the same therapy.
Half of the mice stayed on the ISS for nine weeks to simulate long-term space travel, while the other half returned to Earth after four and a half weeks, arriving at a laboratory within 72 hours. This was the first time in US space flight history that live mice re-entered Earth’s atmosphere and successfully returned to the surface.
According to the study’s findings, the medication “significantly increased bone formation in both flight and ground-control mice without apparent adverse effects.” This therapy has the potential to be a “promising therapeutic to mitigate extreme bone loss from long-duration microgravity exposure.”
Human steps on Mars: Efforts and a roadmap
NASA has been planning a Mars trip that may take nearly two years in the late 2030s or early 2040s. To achieve this, concerns about significant bone density loss in astronauts must be rectified.