Investigating anaemia using human peripheral blood exposed to microgravity

Abstract

Anaemia, characterised by reduced erythrocytes or diminished haemoglobin concentration, results in inadequate tissue oxygenation, leading to symptoms like fatigue and shortness of breath. Space anaemia, an acquired form of anaemia, induced by erythrocyte destruction in microgravity, is not yet fully understood. Expanding our understanding of this condition is vital to enable longer duration space missions. In 2021, the first all-civilians mission - the Inspiration4, launched. Differential expression analysis of RNA raw reads derived from peripheral blood mononuclear cells was conducted to identify globin genes that were perturbed in response to spaceflight, while red blood cell pellets were analysed to quantify haemoglobin fractions using cation-exchange high-performance liquid chromatography to observe how each astronaut’s haemoglobin profile varied before and after spaceflight. Results revealed upregulated globin gene expression post-spaceflight. While no significant differences in haemoglobin fractions were detected, foetal haemoglobin levels showed a slight increase post-flight, followed by delayed adult haemoglobin synthesis. Advancing our understanding of space-induced anaemia is imperative for developing mitigation strategies to ensure the health and safety of astronauts and space tourists when landing on extraterrestrial worlds, where access to medical facilities is limited. Furthermore, microgravity serves as a model for investigating the gamma-to-beta globin switch, offering insights into potential therapeutic strategies for patients diagnosed with beta-thalassaemia and sickle cell disease on Earth.