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

TY - JOUR

T1 - Changes in mitochondrial homeostasis and redox status in astronauts following long stays in space

AU - Indo, Hiroko P

AU - Majima, Hideyuki J

AU - Terada, Masahiro

AU - Suenaga, Shigeaki

AU - Tomita, Kazuo

AU - Yamada, Shin

AU - Higashibata, Akira

AU - Ishioka, Noriaki

AU - Kanekura, Takuro

AU - Nonaka, Ikuya

AU - Hawkins, Clare Louise

AU - Davies, Michael J

AU - Clair, Daret K St

AU - Mukai, Chiaki

PY - 2016/12/23

Y1 - 2016/12/23

N2 - The effects of long-term exposure to extreme space conditions on astronauts were investigated by analyzing hair samples from ten astronauts who had spent six months on the International Space Station (ISS). Two samples were collected before, during and after their stays in the ISS; hereafter, referred to as Preflight, Inflight and Postflight, respectively. The ratios of mitochondrial (mt) to nuclear (n) DNA and mtRNA to nRNA were analyzed via quantitative PCR. The combined data of Preflight, Inflight and Postflight show a significant reduction in the mtDNA/nDNA in Inflight, and significant reductions in the mtRNA/nRNA ratios in both the Inflight and Postflight samples. The mtRNA/mtDNA ratios were relatively constant, except in the Postflight samples. Using the same samples, the expression of redox and signal transduction related genes, MnSOD, CuZnSOD, Nrf2, Keap1, GPx4 and Catalase was also examined. The results of the combined data from Preflight, Inflight and Postflight show a significant decrease in the expression of all of the redox-related genes in the samples collected Postflight, with the exception of Catalase, which show no change. This decreased expression may contribute to increased oxidative stress Inflight resulting in the mitochondrial damage that is apparent Postflight.

AB - The effects of long-term exposure to extreme space conditions on astronauts were investigated by analyzing hair samples from ten astronauts who had spent six months on the International Space Station (ISS). Two samples were collected before, during and after their stays in the ISS; hereafter, referred to as Preflight, Inflight and Postflight, respectively. The ratios of mitochondrial (mt) to nuclear (n) DNA and mtRNA to nRNA were analyzed via quantitative PCR. The combined data of Preflight, Inflight and Postflight show a significant reduction in the mtDNA/nDNA in Inflight, and significant reductions in the mtRNA/nRNA ratios in both the Inflight and Postflight samples. The mtRNA/mtDNA ratios were relatively constant, except in the Postflight samples. Using the same samples, the expression of redox and signal transduction related genes, MnSOD, CuZnSOD, Nrf2, Keap1, GPx4 and Catalase was also examined. The results of the combined data from Preflight, Inflight and Postflight show a significant decrease in the expression of all of the redox-related genes in the samples collected Postflight, with the exception of Catalase, which show no change. This decreased expression may contribute to increased oxidative stress Inflight resulting in the mitochondrial damage that is apparent Postflight.

U2 - 10.1038/srep39015

DO - 10.1038/srep39015

M3 - Journal article

C2 - 27982062

SN - 2045-2322

VL - 6

JO - Scientific Reports

JF - Scientific Reports

M1 - 39015

ER -