Trips to the depths can damage the intestinal functions of the astronaut

NEW YORK, Oct. 3: Exposure to galactic cosmic radiation when traveling in far-flung spaces, such as to Mars, could significantly damage the gastrointestinal functions of astronauts, researchers said, led by a man of Indian origin.

The animal study also raises concerns about the high risk of developing tumors in the stomach and colon.

"Heavy ions such as iron and silicon cause damage due to their higher mass than mass-free photons such as X-rays and gamma (y) scattered on Earth as well as low-mass protons in the Earth. Space, "said Kamal Datta. , Associate Professor at Georgetown University in the United States.

"Even if short trips, such as those that astronauts have made on the moon, are not likely to expose them to this level of damage, the real concern is the lingering injury of a long journey like that of Mars or other missions in the deep space that would be much longer, "added Datta.

The gastrointestinal tract is a self-renewing tissue with continuous cell division / proliferation.

The (upper) mucosal layer of cells is replaced every three to five days by the coordinated migration of new cells from the bottom of a vial-like structure called crypt to the lumen of the intestine.

"Any disruption of this replacement mechanism leads to dysfunction of physiological processes such as nutrient uptake and triggers pathological processes such as cancer," said co-author Albert Fornace Jr., director of the center for NASA's specialized research (NSCOR).

For the study, published in the journal PNAS, the team used the mouse small intestine as a model system and exposed mice to a low dose of ferrous radiation.

They compared the heavy ion group of mice exposed to X-ray-like gamma-irradiated mice and a third unexposed control group.

Scientists have found that intestinal cells in the heavy ion group do not sufficiently absorb nutrients and form cancerous polyps.

Although a very low dose was administered in deep space over several months, the effects of heavy ionic radiation appeared to be permanent, Fornace said.

"It is important to understand these effects in advance so that we can do everything in our power to protect our future travelers from space," said Datta.