UNIVERSITY PARK, Pa. — Funding from the National Institutes of Health will enable a Penn State researcher to study whether vitamin D supplementation could help people ward off or reduce symptoms caused by COVID-19.

Margherita Cantorna, distinguished professor of molecular immunology and nutrition in the College of Agricultural Sciences, received nearly $241,000 as part of a competitive revision to the final year of an existing NIH grant that supports her research on how vitamin D regulates the immune system in the gastrointestinal tract.

Cantorna said the addition of two key collaborators in the college's Department of Veterinary and Biomedical Sciences make the new work possible: virologist Troy Sutton, assistant professor of veterinary and biomedical sciences, and Girish Kirimanjiswara, associate professor whose research focuses on immunology and infectious diseases.

"Patients with acute respiratory infections have been shown to be vitamin D deficient, and vitamin D supplements have been touted as being useful in high doses for preventing seasonal influenza," Cantorna said. "Meanwhile, the emergence of SARS-CoV-2 has generated interest in the potential of high-dose vitamin D supplements to prevent and treat severe disease associated with the COVID-19 pandemic."

Cantorna's research group has shown that vitamin D plays an important role in maintaining health in the gastrointestinal tract. Higher levels of vitamin D reduce susceptibility to inflammatory bowel disease and Crohn’s disease, as well as gut and lung infections in animals and people. However, too much vitamin D can be harmful.

Cantorna noted that the local and systemic inflammation caused by SARS-CoV-2 infection is not well understood, and controlling such inflammation may improve outcomes for COVID-19 patients. Although low vitamin D status has been associated with acute respiratory diseases, research has not confirmed a causal relationship.

"We don't yet fully understand the mechanisms underlying the effects of vitamin D in the lung or how vitamin D regulates host immunity to viral infection," she said. "These significant knowledge gaps have hindered the development of interventions and accurate messaging that include vitamin D for the treatment and prevention of respiratory disease."

Using mouse and hamster models, Cantorna's team will test whether supplemental vitamin D treatments will limit viral replication and/or inflammation in the lung leading to protection against severe SARS-CoV-2 infection.

"We plan to determine the effects, dose and timing of possible vitamin D interventions in infected animals," Cantorna said. "Because SARS-CoV-2 has been shown to infect the gastrointestinal tract, the benefits of vitamin D might include regulation of gastrointestinal immunity as well as lung immunity."

She added that all work with SARS-CoV-2 viruses will be performed at the Eva J. Pell Laboratory for Enhanced Biological Research, which is Penn State's state-of-the-art biosafety level 3 facility.

"In some cases, the most vulnerable people are being told they should take vitamin D supplements to protect against COVID-19, without proof of efficacy or safety," Cantorna said. "We hope our findings can contribute to the development of responsible guidance on whether high amounts of vitamin D are safe and effective in alleviating this disease.