Genetic analysis of the human hair roots as a tool for spaceflight experiments

Abstract

The use of hair roots as experimental samples has been a research focus for understanding the effects of spaceflight on astronauts, because it has many advantages, one of which is the fact that hair matrix cells actively divide in a hair follicle and sensitively reflect the physical conditions of the human body. In 2009, a research program focusing on the analysis of astronauts' hairs was initiated to examine the effects of long-term spaceflight on the gene expression and mineral metabolism in the human body. Since the number of samples per astronaut is limited to 5 strands of hairs at each sampling point, due to the ethical viewpoint of astronauts or limited resources in space, it is important to develop an effective method for the molecular analysis of small amounts of hair roots. In this study, mRNA successfully extracted from 1, 5, and 10 hair follicles was amplified and subjected to the DNA microarray analysis to compare the gene expression within subjects. The results indicated that (1) it was possible to perform the genetic analysis on hair samples stored at −80˚C, even without a fixation buffer and (2) the newly modified method of mRNA extraction and analysis was effective in detecting differential gene expression in samples containing only 5 hairs. In conclusion, RNA was efficiently extracted from 5 hair roots, which is the same number of hair roots used in the space experiment; therefore, this method can be applied to genetically analyze astronauts' hair amples. s

Changes in mitochondrial homeostasis and redox status in astronauts following long stays in space

“…We previously discussed the usefulness of hair follicles in the study of biogenesis23. Our group reported that in some astronauts from the same group examined in this study, genes related to hair growth, such as the fibroblast growth factor (FGF) 18, angiopoietin-like 7 (ANGPTL7) and cartilage oligomeric matrix protein (COMP), were upregulated Inflight.…”

Routine omics collection is a golden opportunity for European human research in space and analog environments

“…Indeed, hair is readily available and easily sampled via extraction of hair follicles, requiring no specific personal expertise nor complex hardware. 97 , 98 Moreover, hair cells can reflect host physical conditions, including human peripheral circadian clock and organismal metabolic responses to environmental changes. 98 Omic studies of astronaut hair are thus beginning to emerge.…”

“… 97 , 98 Moreover, hair cells can reflect host physical conditions, including human peripheral circadian clock and organismal metabolic responses to environmental changes. 98 Omic studies of astronaut hair are thus beginning to emerge. Notably, a seminal study by the Japan Aerospace Exploration Agency (JAXA) conducted transcriptomics on astronaut hair follicles collected before, during, and after 6 months of spaceflight.…”

Histological and Transcriptomic Analysis of Adult Japanese Medaka Sampled Onboard the International Space Station

“…To understand how organisms adapt to the space environment, many experiments can be conducted on humans while they work aboard the Space Shuttle or the International Space Station (ISS) [ 2 , 3 ]. However, various kinds of animal experiments relevant to human physiology are needed to help prevent or solve the health problems astronauts might face.…”