Upregulation of miR-223 in the rat liver inhibits proliferation of hepatocytes under simulated microgravity.

Simulating the microgravity environment of spaceflight altered liver function in mice, and yielded insights into the mechanisms involved. Studies on humans have previously detected impaired liver function after spaceflight, accompanied by bone loss, muscle atrophy, metabolic disorders and cardiovascular problems. Yongjie Chen and colleagues at Shenzhen Graduate School, with co-workers elsewhere in China, simulated microgravity conditions by suspending the animals by their tails, but with their front paws allowing some mobility on the ground. The test animals were found to experience significant changes in established biochemical markers of liver function. An inhibition of liver cell proliferation was also linked to raised levels of a short RNA known to control gene activity.. This research in mice may lead to better understanding of the effects of spaceflight on humans, and suggest ways to maintain good health.