TUESDAY, June 11, 2024 (HealthDay News) -- Astronauts orbiting the Earth tend to suffer from immune system problems such as infections and the reactivation of dormant viruses, even on short-term space flights.

That appears to be because a lack of gravity causes the immune system to go awry during space travel, a new study has found.

Immune cells appear to grow differently in weightless conditions, affecting their ability to fight off disease, researchers report June 11 in the journal Nature Communications.

“We show how simulated microgravity shapes immune cells and how the changes in force alter the cells’ function at the single cell level,” researcher Dr. Daniel Winer, a gerontologist at the University of Southern California’s Buck Institute for Research on Aging, said in a news release.

The researchers also found at least one supplement – the plant pigment quercetin – that can counter the effects of weightlessness on the immune system.

Quercetin reversed about 70% of the immune cell changes caused by a lack of gravity, researchers found. It’s found in red onions, grapes, berries, apples and citrus fruits.

For the study, researchers studied under the microscope how 25 hours of simulated microgravity affected immune cells cultured from the blood of 27 healthy human donors between the ages of 20 and 46.

The researchers grew the cells in NASA’s Rotating Wall Vessel, a piece of lab equipment that simulates weightlessness by gently rotating cell cultures, essentially keeping the cells in a continual state of free-fall.

The team then tested their lab findings against data from prior studies done in humans and mice that had actually gone into space.

Researchers unearthed several genes and biological pathways that are affected by microgravity, and then went searching for specific drugs or supplements that might protect the immune cells.

An AI system designed to detect more than 2 million interactions between genes and different drugs and foods highlighted quercetin as a potential means of boosting the immune system while in space.

“Our work provides a resource to better understand how and why the immune system changes in simulated microgravity and spaceflight,” researcher David Furman, chief of AI at the USC Buck Institute for Research on Aging. “We also provide a way to develop countermeasures to maintain normal immunity under these harsh conditions.”

“This is the first comprehensive study that provides the scientific community worldwide with an atlas to understand human biology in this extreme condition,” Furman added. “The implications are huge, beyond humans in space.”

For example, these changes in the immune system might have things in common with changes that occur as people age, Furman said. Using that knowledge, researchers could investigate therapies that could potentially keep the immune system from weakening as people age.

More information

NASA has more on its Rotating Wall Vessel.

SOURCE: University of Southern California, news release, June 11, 2024