HU Research on Gravity and Inflammation Response Selected for JAXA Feasibility Study

Research Press Release | February 01, 2016

HU Research on Gravity and Inflammation Response Selected for JAXA Feasibility Study

On Earth, neural signals generated through calf muscles send signals that reach the blood vessels of 5th lumbar spinal cord and activate the inflammation amplifier. This opens the gateway for immune cells and allows their access to the central nervous system. However, without gravity, where the gateway will be formed when the experiment is recreated on “Kibo” under a micro-gravity environment is not get known.

Press Release


“Elucidation of the Mechanisms of Inflammatory Reactions in Space”, by Professor Masaaki MURAKAMI of the Hokkaido University Institute for Genetic Medicine, was selected by the Japan Aerospace Exploration Agency (JAXA) for a fiscal year 2015 “Feasibility Study for Use at ‘Kibo’ (General Recruitment Category)”. The project aims to maximize the on-board environment of the Japan Experiment Module “Kibo” in the International Space Station (ISS), to lead the world in producing excellent knowledge and providing results that can become a creative source for scientific and technological innovation for the future. This feasibility study will be performed jointly with JAXA, and will provide further details for the experimental plan and evaluate its technical feasibility.

We have previously reported on the “gateway reflex” in an experimental model using mice, in which a neural signal network is formed as the result of gravitational stimulation applied to calf muscles, leading to the accumulation of immune cells in the blood vessels of the lumbar spinal cord, and thereby causing an inflammation reaction. We also identified an “inflammation amplifier” that is the trigger. At the present time, by using “Kibo” to raise mice in the micro-gravity conditions of outer space, we will investigate changes in the formation of the gateway by which immune cells enter the spinal cord, and in the activation conditions for the inflammation amplifier.

Humans are bound by the Earth’s gravity, yet there has been almost no research on the effect of gravity on our health and wellness. This is because on the surface of the Earth it is difficult to perform experiments under a micro-gravity environment. However, by transferring the experiment to “Kibo”, we will validate the mechanism of the “gateway reflex” for the first time, to prove the importance of gravity on inflammation response. As a result, we may be able to develop methods for controlling inflammation related to various diseases, and manage the health of astronauts. We may also find applications for use on Earth. For example, controlling inflammation by using nerve stimulation equipment containing micro-electrodes implanted in the body that individually stimulate or suppress nerves that control blood vessels. This research will lead to the development of fundamental technologies for the prevention and treatment of diseases and morbidities that are inexpensive, simple, and scientifically-based.


Institute for Genetic Medicine, Hokkaido University

Professor Masaaki MURAKAMI




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