The results showed that both human and animal kidneys undergo "remodeling" by the conditions in space, with specific kidney tubules responsible for calibrating calcium and salt balance showing signs of shrinkage after less than a month in space
A new study led by researchers from University College London (UCL) found that the structure and function of the kidneys change during spaceflight, when galactic radiation causes permanent damage that would endanger any mission to Mars.
The study, published in Nature Communications, is the largest analysis of kidney health in spaceflight to date, and also includes the first health database of astronauts from commercial spaceflight. It was published as part of a special collection of papers in Nature on space and health.
Researchers have known, since the 70s, after humans first went beyond the Earth's magnetic field, and especially when landing on the moon, that space flights cause certain health problems. These problems include loss of bone mass, weakening of the heart and vision, and the development of kidney stones.
Many of these problems are due to exposure to space radiation, such as the solar wind and galactic cosmic rays (GCR) from deep space, which the Earth's magnetic field shields us from on Earth's surface. When most manned space flights take place in low Earth orbit (LEO) and receive partial protection from the Earth's magnetic field, only the 24 people who flew to the Moon were exposed to powerful GCR radiation and only for a short time (6-12 days).
No one has studied the changes that occur in the kidneys and other organs as a result of the conditions that will arise during space flights beyond the influence of the Earth's magnetic field over long periods of time.
In research funded by the Wellcome Trust and Kidney Research UK (KRUK), a UCL-led team of researchers from 40 institutions, from five continents, carried out a series of experiments and analyzes to investigate how the kidneys respond to spaceflight.
The experiment included biomolecular, physiological and anatomical evaluations using data and samples from 20 research groups. The study included samples from more than 40 space missions in low Earth orbit - humans and mice, most of them to the International Space Station, as well as 11 space simulations in the model of mice and rats.
Seven of these simulations involved mice exposed to simulated doses of GCR equivalent to 1.5- and 2.5-year missions to Mars, simulating spaceflight across Earth's magnetic field.
The results showed that both human and animal kidneys undergo "remodeling" by the conditions in space, with specific renal tubules responsible for calibrating calcium and salt balance showing signs of shrinkage after less than a month in space. The researchers say that the likely reason for this is lack of gravity rather than GCR, although more research is needed to determine whether the interaction between lack of gravity and GCR can accelerate or exacerbate these structural changes.
Previously, it was believed that the main reason for the formation of kidney stones during space missions was the loss of bone mass caused by the lack of gravity, which leads to the accumulation of calcium in the urine. Instead, the UCL team's findings indicated that the way the kidneys process salts is fundamentally altered by spaceflight and is likely to be a major cause of kidney stone formation.
A year on the International Space Station, for example, exposes astronauts to a radiation dose that is 50% higher than the five-year limit for nuclear energy workers. The private space mission Inspiration 4, which flew at an altitude of 200 km above the International Space Station, exposed its crew to the equivalent of a nine-month stay on the space station in just three days. A year on the surface of Mars would expose the astronaut to the same radiation as an eyewitness. to the atomic bomb in Hiroshima, and a three-year mission back to Mars is estimated to be six times that (or about 11 thousand photographs x-ray).
Perhaps the most alarming finding, at least for any astronaut considering a three-year round trip to Mars, is that the kidneys of mice exposed to GCR-simulating radiation for 2.5 years experienced permanent damage and loss of function.
Dr Keith Siu, lead author of the study from the Tubular Center (it doesn't sound good. It might be better to keep the original English name of the research institute) in London, UCL School of Renal Medicine, said: "We know what happened to astronauts on missions A relatively short gap has been made so far, in terms of an increase in health problems such as kidney stones. What we don't know is why these problems occur, nor what will happen to astronauts on longer flights like the proposed mission to Mars.
"If we don't develop new ways to protect the kidneys, I would say that an astronaut who flew to Mars might need dialysis on the way back. We know that the kidneys are slow to show signs of radiation damage; by the time it becomes obvious (the signs become clear or the signs are visible), it's probably too late To avoid failure (kidney failure), which would be catastrophic for the mission's chances of success."
The authors say that while the results identify serious obstacles to a mission to Mars, problems must be identified before solutions can be developed.
Prof. Steven B. Walsh, lead author of the study from the UCL School of Nephrology, said: "Our research highlights the fact that if you're planning a mission to space, the kidneys are really important. You can't protect them from galactic radiation with shielding, but the more we learn about the biology of the kidneys , it may be possible to develop technological or pharmaceutical measures to facilitate prolonged spaceflight.
"Any drug developed for astronauts may also be beneficial here on Earth, for example by allowing the kidneys of cancer patients to receive higher doses of radiotherapy, where the kidneys are one of the limiting factors in this regard."
Although the study only describes what happens to the kidneys over a period of up to 2.5 years, this is the most comprehensive data currently available.
Tags: kidneys, astronauts, mars, spaceflight, galactic radiation, kidney health, medical research, UCL, Nature Communications, kidney stones, zero gravity, space missions, astronaut health, GCR radiation, low earth orbit (LEO), station International Space Station (ISS), kidney damage, journey to Mars, kidney function, National Science Foundation, health effects, health in space.
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(It doesn't sound good. It might be better to leave the original English name of the research institute). If you put your comments in other brackets, it will be easier for you to find them before uploading the article/article and at least delete them.
very interesting. The more I read on the subject, the more inclined I am to believe that the first manned mission to Mars will be essentially a suicide mission for the astronauts who will man it.