The SIG Beat


Free Radical Interest Group

Celebration of the 30th Anniversary of the Oxygen Club

NIH’s Free Radical Interest Group and the interagency and university consortium the Oxygen Club of Greater Washington, D.C., work to bring together individuals from a wide range of fields who are interested in understanding the roles that free radicals and other reactive oxygen and nitrogen species play in basic physiology, disease mechanisms, and treatment strategies. The Oxygen Club, founded in 1987 by Daniel L. Gilbert (1925–­2000), was the first group organized to study and discuss free radicals and what is now called “oxidative stress,” in which pathogenic imbalances in the body’s use of oxygen occurs. On October 3, 2017, the Oxygen Club celebrated its 30th anniversary with a symposium in Lipsett Amphitheater (Building 10).

Gilbert was a pioneer in the field of reduction-oxygen reaction (redox) biology. In 1957, when he was a graduate student at the University of Rochester (Rochester, New York), he and Rebeca Gerschman were the first to describe “oxygen poisoning” and link the existence of oxygen-free radicals with damaging effects on biological systems (Science 119:623–626, 1954). Later, as an intramural researcher at the National Institute of Neurological Disorders and Stroke, Gilbert discovered that free radicals impair communication between nerve cells, promote neuroinflammation, and contribute to Alzheimer disease and other disorders. His groundbreaking work on oxygen toxicity laid the foundation for many current extramural and intramural scientific studies.

At the symposium, several people gave talks that emphasized the importance of oxygen and free radicals in biological processes. Gerald Shadel (Yale University, New Haven, Connecticut), who gave the Daniel Gilbert Memorial Lecture, described how mitochondrial reactive oxidative species (ROS) play a role in aging and maternally inherited deafness. He presented new studies that indicate how mitochondrial stress can activate innate antiviral signaling pathways that upregulate DNA damage-resistance genes. He hypothesized that this mechanism acts as a protective signal to prevent ROS-induced damage to the nuclear genome.

Sonia Franco (Johns Hopkins University School of Medicine, Baltimore), who is doing similar research, described how early, innate immune activation from DNA damage is the “canary in the coal mine” that warns the cell of genotoxic danger.

Other presentations highlighted the important role that oxygen plays in cell death. Valerian E. Kagan (University of Pittsburgh, Pittsburgh) explained how oxidized lipids trigger programmed cell death through interactions with metabolic enzymes. And Juliann G. Kiang (Armed Forces Radiobiology Research Institute, Bethesda, Maryland) reported that blood loss (which results in hypoxia) from a wound after radiation injury causes more cell death and damage than blood loss or radiation alone.

Another important aspect of redox biology is the development of tools to measure oxygen in tissue. Murali Krishna Cherukuri, head of the Biophysical Section in NCI’s Radiation Biology Branch, described how his lab is developing noninvasive imaging techniques based on electron paramagnetic resonance (EPR) to measure oxygen concentration in tumors. (Cancer patients with hypoxic tumors are resistant to radiation therapy.) The research findings indicate that EPR imaging could potentially be used to develop effective cancer treatments based on oxygen concentrations in cancerous tissue.

Daniel Gilbert’s spirit of collegial scientific curiosity lives on as the researchers interact with each other—via the interest group and Oxygen Club—and continue to explore the many unanswered questions about oxygen and free radicals.

The interdisciplinary nature of the NIH Free Radical Interest Group and the Oxygen Club of Greater Washington, D.C., provides attendees with the opportunity to both learn and network. Members enjoy a spirit of informality during seminar discussions; many productive collaborations that transcend chemistry, biology, and medicine have begun through these interactions. To receive event announcements and/or to learn more, contact Michael Espey (NCI) at or visit

Scientific Interest Groups

NIH Scientific Interest Groups (SIGs) are assemblies of scientists with common research interests. These groups engage with their members via a listserv; sponsor symposia, poster sessions and lectures; offer mentoring and career guidance for junior scientists; help researchers share the latest techniques and information; act as informal advisors to the Deputy Director of Intramural Research (DDIR); provide advice for the annual NIH Research Festival; and serve as hosts for the Wednesday Afternoon Lecture Series. Most of these groups welcome interested non-NIH scientists. To learn more and see a list of the SIGS, go to