Das Klinikum

Healthy to Mars: Study results point the way for longer and more distant missions into space

Scientist from Tübingen investigates the effects of space travel on the human body with an international space research team

Five U.S. biomedical journals (Cell Press) will publish a coordinated package of 20 European and international scientific studies and collaborations on space exploration on November 25. Daniela Bezdan from the University Hospital of Tübingen is involved in seven publications.

More than 200 scientists from dozens of academic, governmental and industrial institutions and companies, as well as from the aerospace industry, prepared the research work based on the largest set of astronaut and space biology data ever produced. In addition, the scientific work manifests the unique collaboration between the four largest space agencies: NASA (USA), JAXA (Japan), ESA (Europe) and ROSCOSMOS (Russia).

The University Hospital of Tübingen is involved with seven publications by Daniela Bezdan as first author and co-author of publications in the fields of biology, medicine, microbiology and data management. She is a research assistant at the Institute of Virology and Epidemiology of Viral Diseases at the University Hospital.

Influence of radiation and weightlessness on astronauts

Daniela Bezdan's main study focuses on genomically collected data that allow conclusions to be drawn about the influence of radiation and weightlessness on the human body and provide detailed information about the biochemical profiles of 56 astronauts. This number represents ten percent of all astronauts who have ever been in space. The study describes the effects of space travel on the human body and also identifies possible prevention and treatment approaches that could make a longer space flight, such as a mission to Mars, possible.

"Space research is growing and developing rapidly. The progress we have made in space medicine and space biology in recent years is remarkable," says Daniela Bezdan. "Our results on extended telomeres - the protective caps at the chromosome ends - in astronauts in space still amaze us. Our work could also mark a turning point in monitoring the health of astronauts in space using 'liquid biopsy' in the blood: Exosomes and cell-free DNA are tiny biomarkers in the blood that could be obtained anytime on the ISS in a non-invasive way. They enable us to monitor not only human health in space, but also in exceptional situations on Earth," explains Bezdan.

The background to this is the results of the NASA twin study on the two astronauts Scott and Mark Kelly, which investigated the genetic, physiological and behavioral characteristics of identical twins before, during and after Scott's one-year mission in space between 2014 and 2019. Mark Kelly, who was recently elected to represent Arizona in the U.S. Senate, remained on Earth during the mission. The result of the study: Scott's body underwent thousands of molecular and physical changes both during his stay in space and after his return to Earth. For example, the telomeres lengthened in space, but became shorter again after his return to Earth. Extended telomeres are associated with a longer life.

Dr. Christopher Mason, co-author and professor at the Weill Cornell Medicine research facility in New York City, adds: "We can now begin to think at the molecular and cellular level about longer-term missions and also about what drugs, countermeasures and therapies could be used to minimize the health risks to astronauts".

Conclusion

 Daniela Bezdan from the University Hospital of Tübingen and her colleagues in the USA were able to show that space travel leads to an increased concentration of DNA from the mitochondria in the blood plasma. It also affects the exosomes in blood plasma, small vesicles that transport molecules such as DNA and proteins. Since mitochondria are responsible for supplying the cells with energy, an increased stress level during a long stay in weightlessness may have led to the observed increase in concentration. The technology used to measure the so-called cell-free DNA in plasma is currently also being tested for the non-invasive diagnosis of cancer and for monitoring transplanted organs at the University Hospital of Tübingen and Weill Cornell University. 

"I see space research as an opportunity to work with an excellent international team on scientific and medical topics that are not only relevant in space, but also here on Earth. This is why I am committed to promoting Germany as a location for space research, especially in microbiology," Daniela Bezdan concluded.

In addition to her scientific work in Tübingen Virology, Daniela Bezdan represents the University Hospital and Germany as one of three elected coordinators of different organizations in space research: NASA Genelabs Microbiome, Topical Teams ESA Space Omics TT and at ISSOP - International Standards of Space Omics Procedure together with members from NASA (USA), JAXA (JAPAN) and ESA (EUROPE).

In future, Daniela Bezdan will work at the NGS Competence Center Tübingen (NCCT). The NCCT is one of four DFG (German Research Foundation)-funded national sequencing centers for high-throughput sequencing. The center offers automated sample preparation and a broad portfolio of state-of-the-art sequencing technologies. This is complemented by the already established structure as a core facility, the existing infrastructure for data management and the support of bioinformatics.

The following publications will appear in these medical journals on November 25, 2020: Cell, Cell Reports, iScience, Cell Systems and Patterns. Also online at https://www.cell.com/c/the-biology-of-spaceflight

 Original publication:

Cell-free DNA (cfDNA) and exosome profiling from a year-long human spaceflight reveals circulating biomarkers
 Daniela Bezdan, Kirill Grigorev, Cem Meydan, Fanny A. Pelissier Vatter, Michele Cioffi, Varsha Rao, Kiichi Nakahira, Philip Burnham, Ebrahim Afshinnekoo, Craig Westover, Daniel Butler, Chris Moszary, Matthew MacKay, Jonathan Foox, Tejaswini Mishra, Serena Lucotti, Brinda K. Rana, Ari M. Melnick, Haiying Zhang, Irina Matei, David Kelsen, Kenneth Yu, David C Lyden, Lynn Taylor, Susan M Bailey, Michael P.Snyder, Francine E. Garrett-Bakelman, Stephan Ossowski, Iwijn De Vlaminck, Christopher E. Mason

doi: https://doi.org/10.1101/2020.11.08.373530