- A special form of vitamin D – not found over the counter (OTC) – may be able to fight inflammation in the lungs caused by immune cells, a new study suggests.
- Research shows that vitamin D has an inflammation ‘deactivation’ mechanism, which may work in severe cases of COVID-19.
- However, clinical trials are needed before vitamin D is adopted to treat COVID-19 or other respiratory illnesses.
- Researchers warn of people taking more than the recommended amount of vitamin D in the hopes of avoiding infection with COVID-19.
Scientists share insight into how vitamin D could help severe cases of COVID-19 by revealing how the vitamin works to reduce hyper-inflammation caused by immune cells.
A new joint study from Purdue University and the National Institutes of Health (NIH) demonstrates how an active metabolite of vitamin D – not an over-the-counter form – is involved in “stopping” inflammation in the body during infections such as COVID-19.
“Since inflammation in severe cases of COVID-19 is a key cause of morbidity and mortality, we decided to take a closer look at the lung cells of COVID-19 patients,” the lead authors said, Dr. Behdad (Ben) Afzali, Head of the Immunoregulation Section of the National Institute of Diabetes and Digestive and Kidney Diseases, NIH, and Dr. Majid Kazemian, Assistant Professor of Biochemistry and Computer Science at Purdue University .
The study appears in the journal
As part of the study, researchers analyzed individual lung cells from eight people with COVID-19.
They found that in these cells, part of the immune response to SARS-CoV-2 – the virus that causes COVID-19 – flares up and exacerbates inflammation in the lungs.
After administering vitamin D in test-tube experiments, they observed a reduction in inflammation of lung cells.
They then delved into how the vitamin achieves this.
To do this, they turned to helper T cells, also called CD4 + cells, which are a type of immune cell that stimulates “killer” T cells and other white blood cells to trigger an immune response.
T cells are known to play a role in severe and dangerous cases of COVID-19 by putting themselves into overdrive and leading to an often fatal phenomenon known as a cytokine storm.
Normal infection vs. COVID-19
Scientists have found that in normal infections, Th1 cells, which are a subset of T helper cells that fight microbes inside the cell, go through a pro-inflammatory phase. During this phase, the body clears the infection.
Shortly after, the system shuts down to enter the anti-inflammatory phase.
Scientists have found that vitamin D is essential for speeding up this transition.
“We found that in healthy T cells, the activation of the inflammatory gene program coincided with the activation of a vitamin D system within these cells. So we studied how this vitamin D system works and what it does for healthy T cells before trying to link it to COVID-19, ”said Dr Afzali and Dr Kazemian. Medical news today.
While in COVID-19 infections, scientists found that the pro-inflammatory phase of Th1 cells did not stop. They attributed this to vitamin D deficiency or an abnormal cellular response to vitamin D.
“As expected, by studying which genes were ‘turned on’ in immune cells in the lungs of eight patients, we found that their cells were in an inflammatory state,” said the coauthors.
Dr Afzali and Dr Kazemian said they were somewhat surprised to identify the intracellular system of vitamin D.
“[T]Traditionally, vitamin D has been believed to depend on the kidneys to activate it before it becomes functional. We found that T cells have an autonomic system to both fully activate and respond to vitamin D, independent of the kidneys, ”they said.
The researchers speculated that adding a highly concentrated intravenous metabolite of vitamin D to existing treatments could further help people recover from COVID-19. But they have yet to test this theory in clinical trials.
But the authors stress that people shouldn’t take these findings as a recommendation for treatment, and a lot more work is needed.
“[I]It is extremely important to note that this study did not test vitamin D treatment in humans, but analyzed lung cells from eight people with severe COVID-19, ”said Dr Afzali and Dr Kazemian.
“The results, while interesting, should not be interpreted as indicating that vitamin D is beneficial for the prevention or treatment of COVID-19 or that it is a substitute for other preventive and effective means of preventing COVID. -19, including vaccines, masks, and social distancing. “
– Dr Ben Afzali and Dr Majid Kazemian
Dr Donald J. Alcendor, associate professor of pathology, microbiology and immunology at Vanderbilt University School of Medicine, said the study offered clues to a possible mechanism that will require larger-scale validation .
“The general public widely believes that taking megadoses of vitamin D can protect you before or after testing positive for COVID-19. The science to support these claims is still evolving and will require a large-scale control clinical trial in the future. More so, the mechanism by which vitamin D affects COVID-19 is still unknown, ”he said.
Dr Alcendor said that although vitamin D is known to have immunomodulatory functions, it does not justify its use as a protective measure against COVID-19 infection, especially if one ignores mitigation practices. COVID-19.
He warned that attempting to take higher doses of fat-soluble vitamins such as vitamin D could be problematic for some people.
“A normal diet with a daily generic multivitamin will provide you with the vitamin D you need,” he said.
The study suggests that vitamin D could be a treatment option for COVID-19 thanks to its role in hyper-inflammation.
“This study reveals a potentially unique role that vitamin D plays in activating the functions of T cells that regulate inflammation in COVID-19, and understanding these regulatory pathways may provide information that will lead to the development of new therapies. for the treatment of COVID-19, ”said Dr Alcendor.
“This key discovery could lead to the development of new therapies for several respiratory viruses. The potential of this study could be revolutionary.
– Dr Donald Alcendor
Dr Kazemian and Dr Afzali argue that we will have to wait for the results of clinical trials.
“There are a number of clinical trials that are actively studying the potential of vitamin D as an adjunct therapy for the treatment of COVID-19. When these studies are published, we will have a much better idea of the therapeutic role that vitamin D could play in the inflammation caused by COVID-19, ”they said.
However, Dr Alcendor said future research should answer a multitude of questions:
“[I]s is this mechanism specific to COVID-19, or is it true for other respiratory infections? If this study were done with samples from influenza patients, would you get a similar result? Could this key discovery provide information that would lead to new therapies for several respiratory viruses? ”