Humans thrive on Earth, so there is a high risk of health problems once we leave the environment. The team from the University of California, Riverside, and San Diego recently found new evidence to support this view. Microgravity simulations show that if you stay in space for a while, the body’s intestines “leak” and increase the risk of contracting certain diseases after a few weeks.
The human digestive system is a very extreme place. Not only is it filled with stomach acidthat that dissolves other organs, but it also contains a vast ecosystem of microorganisms that can cause many dangers if they escape into other parts of the body. To ensure our safety, our intestines are lined with epithelial cells that form a non-permeable barrier to bacteria and other nostrils.
In a healthy human body, epithelial cells should be impermeable. However, sometimes due to disease, poor diet and weakening can lead to a variety of chronic diseases, such as type 1 diabetes, inflammatory bowel disease and liver disease.
For the new study, the team hopes to investigate whether microgravity in space affects this barrier in the human gut. Studies have shown that because of low gravity and high radiation, space travel can weaken astronauts’ bones and muscles, induce dementia, increase the incidence of cardiovascular disease, and even alter gene expression.
To study the effects on the intestines, the researchers developed intestinal epithelial cells in a fast-rotating bioreactor to simulate the effects of microgravity. After working in this environment for 18 days, the team stopped rotating and examined the cells.
In this case, it was found that epithelial cells delayed the formation of a “close connection” that connected the cells. As these connections weaken, the walls become permeable or “leaking”, which the team then demonstrates using acetaldehyde. It is well known that this alcohol metabolite usually weakens the barrier, and microgravity cells are difficult to escape these effects.
Lead researcher Declan McColl (UCR School of Medicine/Carrie Rosema)
Declan McColl, lead researcher on the study, said: “Our study is the first to show that the microgravity environment prevents epithelial cells from resisting the effects of drugs that weaken the properties of these cell barriers. Importantly, we observed that the defect was retained for up to 14 days after removal from the microgravity environment. “
The team says the findings could have an impact on the health of astronauts in space even after returning to Earth. Unfortunately, the gut seems particularly prone to problems – another recent study in mice found that cosmic radiation affects the ability of intestinal cells to absorb nutrients and increase the risk of cancer.
All in all, space travel seems to be a great burden on the human body. At the moment, it seems safer for most of us to stay on Earth.
The study was published in the journal Scientific Reports.
Source: University of California, Riverside