The Gut - Lung Axis?

Over the past few decades our knowledge and understanding of the teaming population of microorganisms, or microbiome, that live in and on our bodies has expanded. We now realize that not only is our gut home to a microbiome, but other organs and tissues have their own microbiomes, such as our skin, eyes, and lungs to name a few.

In addition to the existence of various microbiomes, we also understand that these populations are an integral part of our defense systems, as well as our health and wellbeing. It is also becoming clear that our microbiomes are not independent and distinct, instead, they are interconnected and work together to form axes of communication.

The gut-brain axis is something we have written and blogged about, but another axis that is rising in prominence is the Gut - Lung axis.

What is the gut-lung axis?

The gut-lung axis suggests that alterations of gut microbiota communities have an effect on lung health and disease. As the lungs are exposed to the outside as we breathe, they develop a community or microbiome. Through interactions with our cells and the compounds they produce, these communities communicate with other microbiomes such as the gut. As in the gut, the lung microbes also make compounds that can also act like drugs, to maintain lung health and discourage opportunistic pathogens.

What is the Gut - Lung Axis important?

A recent collaborative study between Cedars-Sinai Medical Center, Los Angeles, and Mayo Clinic, Rochester, showed that fungi, such as aspergillus, penicillium, or Alternaria, that are important in asthma are also part of the human gut mycobiome. The study showed that if there are changes to these specific fungi in the gut, then that has an impact on asthma development, even though these fungi may not be present in the lungs. This indicates that changes to the gut microbiome can be felt in the lungs.

Since the start of the COVID19 pandemic in 2019, we have learned a lot about SARS-CoV2, the virus that causes COVID19. One of the ways it infects people is through receptors on cells in our gut. A recent Brazilian study by the São Paulo State University and the Ribeirão Preto Medical School, University of São Paulo, recommended that by improving the health of our microbiome we could reduce the severity of COVID19 infection. This will not necessarily prevent infection but may help to blunt or significantly reduce the severity of infection.

Bottom Line!

Taken together recent research has shed new light on the complexity and interconnectedness of the various microbiomes that exist in and on the human body. Although there is still much to learn, it is clear that these organisms play an important role in our health are something we should nurture and pay close attention to.