NASA - National Aeronautics and Space Administration

Graduate student Jordan Spatz, left, pictured with Dr. Paola Divieti Pajevic, right, one of the winners of the National Institutes of Health BioMed-ISS grant for her proposal on the study of bone cells in microgravity. (Photo courtesy of Dr. Divieti Pajevic) The National Institutes of Health (NIH) Biomedical Research on the International Space Station (BioMed-ISS) is funding three proposals for space station research. Dr. Divieti Pajevic, an Assistant Professor of Medicine at Harvard Medical School and a member of the Endocrine Unit at Massachusetts General Hospital in Boston, is the lead for one of the winning proposals. Her investigation will use microgravity to study bone density loss, whether from disuse or disease. The NIH selected the final proposals because of their value in using space to make discoveries that can improve human health on Earth.

Dr. Divieti Pajevic's experiment takes advantage of the effect of microgravity on living systems. She will research osteocytes, the most plentiful cells in bones, which maintain bone tissue and are thought to have gravity sensing abilities. The effects of low-gravity on these cells are linked not only to astronaut bone loss due to weightlessness, but also to bone loss resulting from immobility in humans on Earth. According to Dr. Divieti Pajevic, "The International Space Station, with its unique microgravity environment and minimal fluid shear culture conditions, will be our 'proof-of-principle' of the models developed in the lab."

This BioMed-ISS experiment specifically looks at gene regulation in osteocytes and how gravitational forces, or lack thereof, influence bone density regulation. Conducting microgravity experiments on these cells can provide more detailed information about osteocyte remodeling properties, using specific in vitro models developed by Dr. Divieti Pajevic and her team: Jordan Spatz, Dr. Lisa Freed, Chris Adamson, Lowell Misener, and Dr. Clemens Bergwitz.

The formation of therapeutics to combat skeletal diseases, whether resulting from disuse or immobilization, depends on an understanding of the mechanisms of mechanotransduction -- the physiological process where cells sense and respond to mechanical loads, including those from gravity -- in osteocytes at the cellular and molecular level. The knowledge from this study may lead to methods to halt bone loss and even develop or remodel lost bone. According to Dr. Divieti Pajevic, "[The BioMed-ISS osteocyte experiment] will help to advance insights into osteocyte biology, leading to improved treatment options for the millions of Americans suffering from disuse-induced bone loss."

Dr. Divieti Pajevic is also a recipient of the A. Jee Memorial Young Investigator Award, the John Haddad Young Investigator Award, and the Clafilin Distinguished Scholar Award. Congratulations to Dr. Divieti Pajevic on her award winning proposal, and also to the other NIH grant recipients: Dr. Declan McCole and Dr. Millie Hughes-Fulford. by Jessica Nimon
NASA's Johnson Space Center
International Space Station Program Science Office