Welcome to brain Stuff from how Stuff Works, Hey, brain Stuff, Lauren Vogel bomb here. When a SpaceX supply mission recently visited the International Space Station, it's five thousand, eight hundred pounds. That's two thousand sixty kg of cargo. Included equipment for studying thunder storms from the vantage point of space and growing vegetables in orbit, the sort of stuff you'd expect astronauts to need for their research. But tucked in with
those items was something more unusual. Containers with samples of frozen sperm from twelve anonymous human donors obtained from a California sperm bank, along with six samples of sperm from breeding bowls. Those samples will be used in a planned experiment micro eleven Astronauts will fall the sperm and add chemicals that trigger activation of movement and preparation for fusing with an egg. Then they'll put the sperm under a microscope so they can capture video footage of the sperm swimming.
In addition, they'll preform chemical tests. Meanwhile, back on Earth, other researchers will be performing these same tests on identical samples of spermphore comparison. The experiment is designed to study sperm motility, that is, the ability to move and swim in microgravity conditions, and how successful they are in triggering the physiological changes known as capacitation, which enables them to
penetrate and fertilize eggs. That information could help to answer the question of whether humans would be capable of reproducing if they settle in future colonies on the Moon or Mars, or if they venture on even longer journeys into the cosmos. We spoke with Joe tash And, emeritus professor in the Department of Molecular and Integrative Physiology at the University of Kansas Medical Center. He said, if you don't have healthy sperm,
you've got real risk to multigenerational survival in space. Dash was the lead scientist in developing the experiment and continues to be involved as a consultant. NASA has been conducting research on reproductive and developmental space biology since the nineteen nineties, According to an email from researchers at NASA's AIMS Research Center in California Silicon Valley who are involved in the micro eleven research. In one study published in a March
issue of Proceedings of the National Academy of Sciences. For example, female frogs aboard a space shuttle were induced to ovulate so their eggs could be fertilized. The study demonstrated that gravity induced rotation of the zygote, that's the cell formed by the fusing of a sperm and an egg, wasn't necessary to develop a free swimming tadpole with a normal body.
Micro eleven marks the first time that human sperm have been launched into space, that is, aside from the ones inside male astronauts bodies, though there have been previous research efforts involving animal sperm. Back in the nineteen eighties, German researchers launched full seamen into space on a suborbital rocket that briefly subjected them to a minute and a half of weightlessness, which was recorded on video. Tash says then in Tash and colleagues sent samples of sea urchin sperm
on two space Shuttle missions. In those two experiments, it wasn't possible to shoot video under a microscope, so instead they looked at signal transduction, the molecular mechanism within the sperm cell that tells it when to start wiggling its tail. The results of the German study and Tash's research both found that sperm actually swam faster in microgravity than they do back on Earth. But in one of Tasha's experiments, he detected what maybe a big hindrance to procreating in space.
When sea urchin sperm were exposed to chemical compounds called peptides that would be released by eggs, the signaling that triggers capacitation, an essential part of reproduction, occurred much more slowly. The micro eleven experiment will gather data on the effects of microgravity on swimming and capacitation in separate trials. According to Tash, but microgravity isn't the only factor that could
influence reproduction in space. Outside of the Van Allen Belts that shield Earth from high energy particles from space radiation, exposure could create serious problems. A study published in a May seventeen issue of Reproduction found that exposure to charged particles of the sort found in space damaged the ovaries
of female mice. We spoke via email with the studies corresponding author, Eureka Luteraier, a professor of medicine, developmental and cell biology, and public health at the University of California, Irvine. She said, our research found the finite ovarian follical reserve is depleted by exposure to charged oxygen or iron particles, which are components of galactic cosmic rays. This damage is irreversible and will result in early onset of a variant
failure or premature menopause. Additionally, Luteraire said that human and animal studies provide evidence that exposure to gamma radiation and charged iron particles decreases sperm motility. But even if it's possible to conceive in space, pregnancy and childbirth could be problematic.
Chris Lenhart, a senior faculty member at the Baylor College of Medicine Center for Space Medicine, says in an email that it's not known how well an embryo would develop in the environment of space, or whether natural birth would be possible. Today's episode was written by Patrick Jake Tiger and produced by Tyler Clay. If you enjoy our show and also not being Naked, check out our online shop
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