RNAseq analysis of rodent spaceflight experiments is confounded by sample collection techniques

This research study aimed to understand how space travel affects the human body by using a special kind of mouse called rodents as stand-ins for humans in experiments that mimic conditions astronauts might face, like different gravity and cosmic radiation. Scientists studied changes in these "spaceflight" mice's muscles (like their quadriceps) and liver to see how they responded compared to normal ones on Earth. To do this study, the researchers took samples of tissue from both types of mice after exposing them to conditions similar to space travel for a certain period. They then examined these samples at different times using advanced technology that looks closely into our genes and how they work in real-time (a process called RNA sequencing). The goal was to see if there were any changes or damage caused by the simulated space environment, which could help us understand potential health risks for astronauts.

In this study published in iScience on December 18, 2020, researchers investigated the effects of spaceflight-induced stressors such as altered gravity fields and cosmic radiation exposure on human physiology using rodent models. The primary focus was to understand how these conditions impact muscle structure in liver tissues by analyzing gene expression patterns through RNA sequencing (Ribodepletion method). The study involved the collection of both quadriceps and liver samples from groups 1-4, which were exposed to spaceflight environments. Total RNA was extracted directly onboard a research facility aboard the International Space Station (ISS) using an automated Ribodepletion system designed for in situ processing under microgravity conditions. The integrity of these tissue samples and their gene expression profiles were then evaluated back on Earth to ensure accurate representation of spaceflight-induced changes at both molecular and structural levels within the liver and muscle groups studied (quadriceps).