Simulating Parabolic Flight like g-Profiles on Ground - A Combination of Centrifuge and Clinostat

Clinostats and centrifuges are widely used to create simulated microgravity or hypergravity, respectively, in order to study the impact of gravity on biosystems. Here, we used a clinostat and a centrifuge in alternating modes of operation in order to create a simulated parabolic flight like g-profile. To our knowledge, it is the first time that both devices were run in connection. In order to test the method, we investigated the production of reactive oxygen species of immune cells (macrophages) during oxidative burst in an on-line kinetic approach, which has been extensively studied under real (parabolic flight) and simulated microgravity (clinostat) as well as under hypergravity conditions (centrifuge). Our results indicate that clinostat and centrifuge can be operated in an alternating way to simulate the repetitive changes of gravity during parabolic flight. Although the switch from one gravity level to the other could not be carried out as quickly as it takes place during actual parabolic flight due to technical and operational reasons, it can be concluded that running experiments in a clinostat aboard a centrifuge on ground are suitable for studying gravity-related phenomena