Scientists have learned more about how SARS-CoV-2 infections, which cause COVID-19, can ruin the ability of immune cells to repair lung damage. This could help explain some of the symptoms experienced by long COVID patients. The research has also identified a potential treatment for long COVID and damage from other acute and chronic respiratory infections. The work has been reported in Science.
In this study, the researchers discovered that severe lung infections, such as COVID-19 can severely damage structures called peroxisomes in certain immune cells known as macrophages. These cells are typically on the front lines of infection, and can identify and destroy invaders, and help orchestrate repair after damage to lung tissue. But it seems that when peroxisomes are not functioning properly in macrophages, they stop functioning properly.
The investigators also found that the function of these aberrant peroxisomes could be boosted with a drug called sodium phenylbutyrate, and this can help the immune system get back to repairing lung damage. This drug has also already been approved by the US Food and Drug Administration (FDA) for the treatment of unusually high blood ammonia levels.
"COVID-19 can leave the lungs unable to heal properly by damaging these tiny structures inside our cells. Our discovery is important because it not only explains why some people continue to have breathing problems long after their initial illness but also points us toward a potential treatment to help them recover by targeting a tiny organelle inside critical immune cells," said senior study author Jie Sun, Ph.D. of the University of Virginia School of Medicine.
"A tiny organelle can have big roles. I hope our work could lead to new peroxisome-centric therapies that can help people suffering from long COVID."
Peroxisomes normally work to help break down toxins and fats that are found in cells. This study has indicated that they may also have other roles, such as reducing inflammation following serious lung infections. As such, they could be useful in treating lung problems.
While more research will be needed to determine whether sodium phenylbutyrate may be a good treatment for long COVID or other lung infections, this study has shown that it has promise.
Now, the scientists are working with clinicians to learn more about how peroxisomes may be related to long COVID or other lung diseases, Sun added. "Ultimately, we want to develop peroxisome-targeting therapies to give patients the chance to breathe more easily again and get back to their normal lives."
Sources: University of Virginia, Science
