Respiratory Health and the Microbiome: The Gut-Lung Axis

Respiratory Health and the Microbiome: The Gut-Lung Axis

Respiratory conditions, both chronic and acute, are some of the most common issues seen in clinical practice. In 2016, chronic obstructive pulmonary disease (COPD) alone accounted for around 3 million deaths, and was the third leading cause of death worldwide.  Asthma is one of the most common chronic diseases globally affecting nearly eight percent of people (over 24 million) in the US alone.  Childhood onset of asthma can impair airway development, and persist into adulthood. Adult asthma may accelerate the decline of pulmonary function, and increase susceptibility to infection. Both children and adults with severe asthma have impaired innate antiviral immunity with altered cytokine responses, and increased risk of hospitalization. Comorbid conditions are common, with almost two-thirds of those with asthma having at least one comorbidity. The most common comorbidities are diabetes, osteoporosis, metabolic syndrome, cardiovascular disease, and mental illnesses. Lower respiratory infections were the 5th leading cause of death and the leading cause of infectious death globally in 2015.

With the prevalence of both chronic and acute respiratory illnesses, it is in the best interest of our patients to identify and address root cause and practice prevention.  Accumulating evidence has highlighted the influence of the gut microbiota on lung immunity — the gut-lung axis — and current research has drawn a strong correlation between dysbiosis of several anatomical areas and pulmonary health or disease. Here is a synopsis of current research focussing on the microbiome, the Gut-Lung Axis, and their roles in pulmonary health.

• Every chronic lung condition exhibits an altered pulmonary microbiome – Asthma, COPD, pneumonia, cystic fibrosis and all other chronic lung diseases have an unhealthy balance of beneficial and pathogenic organisms.  Imagine if we could effect change there.
• The microbiome influences the host immune system – Beneficial microorganisms in the gastrointestinal tract assist in the development of healthy immune function including defense through regulation of T cells, systemic inflammation and tolerance.  Pathogenic organisms contribute to immune imbalances and a shift toward allergy and autoimmunity.
• Immune cells in the lungs recruit from primed immune cells in the gastrointestinal (GI) lymphatics – What a beautiful design!  When we get exposure to a pathogen in the sinuses, mouth and throat, the bugs are swallowed and read by the lymphatics in the gut (Gut-associated lymphoid tissue, or GALT), which then produce an artillery of defenses just in case an infection occurs.  When it does, the immune system in the lung actively recruits those defenses to fend off illness.⁵
• The gut and lung microbiota contribute to exacerbations of lung disease – Gastrointestinal dysbiosis can contribute to oral and pulmonary dysbiosis, all of which can result in exacerbations of lung disease.⁵ One study reported that more than 70 percent of people with severe lung disease also have gastroesophageal reflux disease (GERD), a common association with GI dysbiosis.
• The microbiome of the lung (no – it’s not sterile!) is most closely associated with the oral microbiome – During sleep, microaspiration of saliva occurs, resulting in the transfer of bugs from the mouth to the lungs.  Since plaque and periodontal pockets are sources of microorganisms, oral hygiene and the oral microbiome need to be tended as well.
• The gut microbiota contributes to acute lung injury – Bacterial metabolites, such as lipopolysaccharides (LPS), mediate systemic inflammation and tissue injury via stimulation of toll-like receptor 4 (TLR4) receptors.  Keeping endotoxin producing bugs in check can assist in maintaining a balanced immune/inflammatory response, with just the right amount of gas and brakes to keep us healthy.⁵
• The vagus nerve is involved  – When the vagus nerve is sending healthy signals, it prevents shock induced organ injury – including in the lungs – and prevents gut barrier injury.⁵ However, gastrointestinal dysbiosis can result in damage to the vagus nerve as endotoxins migrate to the brain and cause inflammation.  Another reason to keep those GI bugs in good balance.
• Beneficial microorganism reduce systemic inflammation – Production of short chain fatty acids such as butyrate and acetate by beneficial bugs helps to reduce inflammation throughout the whole body, establishing balanced and effective immune activity .⁶

As clinicians, we are always on the lookout for clinically effective products and practices.  One such product that targets not only the entire GI tract but the entire body and supports microbiome balance is Biocidin.  Biocidin is a synergistic combination of botanicals, with a track record of more than 30 years.  It got its start on the Comprehensive Digestive Stool Analysis (CDSA) panel for a prominent laboratory (with inclusion on more than 250,000 tests), and is renowned for its ability to help manage and balance the gastrointestinal microbiome.  However, its clinical applications are numerous, and not limited to the gut.  The formula has three distinct mechanisms; maintaining healthy microbial balance, supporting immune function and cleansing biofilms.  The liquid formula is easy to administer and provides activity in the oral cavity as well as the gut.

We can also support our patients by educating them about the importance of oral care, and its effect on the oral and distal microbiome. Dentalcidin is a natural toothpaste with the added boost of broad-spectrum botanicals to support immune defense and a healthy microbial balance. It is an easy way to bolster the mechanical function of toothbrushing, it tastes great, and it is something your patients are already doing.  Bio-Botanical Research has also created an oral rinse to compliment Dentalcidin, for deeper activity.

References

1. https://www.statista.com/topics/4339/chronic-obstructive-pulmonary-disease-copd-in-the-us/#dossierSummary__chapter1
2. https://www.frontiersin.org/articles/10.3389/fped.2019.00246/full
3. https://www.healio.com/news/infectious-disease/20170829/lower-respiratory-tract-infections-remain-leading-infectious-cause-of-death-worldwide
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4751994/pdf/nihms756902.pdf
5. https://www.tandfonline.com/doi/full/10.1080/1040841X.2016.1176988
6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4595839/
7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4751994/pdf/nihms756902.pdf
8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4751994/pdf/nihms756902.pdf
9. https://journals.physiology.org/doi/full/10.1152/ajpgi.00412.2001