The Gut Microbiome and Ozone-induced Airway Hyperresponsiveness. Mechanisms and Therapeutic Prospects

In recent years, several new asthma therapeutics have been developed. Although many of these agents show promise in treating allergic asthma, they are less effective against nonallergic forms of asthma. The gut microbiome has important roles in human health and disease, and a growing body of evidence indicates a link between the gut microbiome and asthma. Here, we review those data focusing on the role of the microbiome in mouse models of nonallergic asthma including obese asthma and asthma triggered by exposure to air pollutants. We describe the impact of antibiotics, diet, and early life events on airway responses to the air pollutant ozone, including in the setting of obesity. We also review potential mechanisms responsible for gut-lung interactions focusing on bacterial-derived metabolites, the immune system, and hormones. Finally, we discuss future prospects for gut microbiome-targeted therapies such as fecal microbiome transplantation, prebiotics, probiotics, and prudent use of antibiotics. Better understanding of the role of the microbiome in airway responses may lead to exploration of new microbiome-targeted therapies to control asthma, especially nonallergic forms of asthma.