Technologies and Analyses Using Medaka to Evaluate Effects of Space on Health

Abstract

Operation of the International Space Station (ISS) has begun. It is important for astronauts to stay healthy and comfortable in space. Reducing influences of environmental stress on astronauts during space flight is a subject of space medicine. With this background, we at the Japan Aerospace Exploration Agency (JAXA) Space Biomedical Research Office (J-SBRO) conduct research to understand and address the effects of the space environment on human health. Although the abovementioned research is of great importance to human health, it is often very difficult to verify by clinical research alone. Especially the effect of radiation is one issue becoming increasingly important due to the continuous accumulation of space radiation during long-duration stays in space. With their ease of breeding and transparent development, small teleosts are good model organisms. Medaka, the vertebrate, is an ideal model for space medicine. We are using medaka, which have a wider range of the habitat conditions, such as breeding temperature, than zebrafish, and have a history in radiation research, to verify the effects of the space environment. In this review, we are going to introduce medaka experiments at a cellular, tissue, and individual level for space medicine.

Static and Dynamic Hypergravity Responses of Osteoblasts and Osteoclasts in Medaka Scales

“…For example, fluorescent protein markers of osteoblasts can be observed in vivo (Inohaya et al, 2007). Furthermore, the launch of the aquatic animal habitation module (Aquatic Habitat), which is planned for the near future, will enable breeding medaka in the International Space Station (Sakimura et al, 2003;Watanabe-Asaka et al, 2010). We will be able to perform space experiments using the scales of space-bred medaka, both in vitro and in vivo, in the near future.…”

“…Its relatively short life cycle and high productivity (Kasahara et al, 2007;Kawakami, 2007;Takeda, 2008) are also valuable features. Therefore, medaka appears to be a model organism that can be used to analyze various biological processes, including bone metabolism, at the molecular level (Inohaya et al, 2007;Watanabe-Asaka et al, 2010). Medaka were launched into space in 1994 as part of a microgravity experiment (Ijiri, 1995).…”

Educational Value of Experiments on Life Support Systems with Ground-Based Aquatic Habitats

“…12 " A recent initiative by the Japanese Aerospace Exploration Agency (JAXA) plans to include an aquatic habitat in their International Space Station module, Kibo. 13…”

A FAM-based Switched Control Approach for the Automation of Bioregenerative Life Support Systems

“…A recent initiative by the Japanese Aerospace Exploration Agency (JAXA) plans to include an aquatic habitat in their International Space Station module, Kibo. 16 Beyond these efforts, very little has been done to make use of aquatic habitats for research in spaceflight life support control and automation.…”