Mighty Mice Flying on Dragon

NASA is sending some buff moustronauts to the International Space Station. These “Mighty Mice” will ride aboard SpaceX’s Dragon cargo capsule on top of a Falcon 9.

But Why?

In the (hopefully) not too distant future, people other than astronauts will begin living and working in space. One of the most glaring problems we face is what happens to the human body in space. We’re going to have to get a handle on the fact that we tend to lose muscle mass and bone density when we don’t have to fight gravity all day.

Hopefully, we’ll build big artificial gravity rings someday, but in the meantime, we need to understand this problem. And wouldn’t it be nice if we could actually counteract the muscle and bone loss?

That’s where the mice come in. As explained by Se-Jin Lee, M.D., Ph.D. and Emily Germain-Lee, M.D. during NASA’s What’s On Board presentation, some of these mice were engineered to not produce a protein called myostatin, which blocks muscle growth. Some of the other other mice produce the protein naturally, but are given a compound to block it. This makes it so their muscles are never told to stop getting bigger.

There’s also a couple other groups of mighty mice, and some regular lab mice, which won’t be receiving any treatment to fight the muscle and bone loss, so they can be compared to the treated mice.

We weren’t able to find any photos of the mice being sent up on Dragon, but the one below shows a bull that was identified as having a naturally occurring mutation in the myostatin gene. As you can see, when myostatin is missing from the equation, the muscles keep growing past normal limits.

Bull with naturally mutated myostatin gene. Credit: NASA

The drug being used to block myostatin will also block activin, which inhibits bones growth. The goal here is see if the treated mice are able to maintain their muscle mass and bone density during their time in microgravity. This treatment could be a major breakthrough in the general health and well-being of anyone living in a microgravity environment. It might help lead to a treatment for spacebound Earthlings, so we can remain strong while we’re floating around up there.

Micro CT images show bones from normal mice (top) and bones from mice treated with the experimental drug. Credit: NASA

In addition to helping astronauts, patients on the ground could also benefit from a treatment like this. You can imagine how someone who is suffering from disuse, muscular dystrophy, cancer, heart disease, osteoporosis, and other disorders might welcome a treatment that would keep there muscles and bones from wasting away. Like many things NASA does, this could greatly benefit the lives of folks living on Earth.

There are lots of other health issues related to spaceflight that will have to be solved, like cardiovascular and eye problems, but one step at a time. Well, lots of steps at a time, because NASA is working on those, too. 😉