Targeting Lung–Gut Axis for Regulating Pollution Particle–Mediated Inflammation and Metabolic Disorders

Abstract

Cigarette smoking (CS) or ambient particulate matter (PM) exposure is a risk factor for metabolic disorders, such as insulin resistance (IR), increased plasma triglycerides, hyperglycemia, and diabetes mellitus (DM); it can also cause gut microbiota dysbiosis. In smokers with metabolic disorders, CS cessation decreases the risks of serious pulmonary events, inflammation, and metabolic disorder. This review included recent studies examining the mechanisms underlying the effects of CS and PM on gut microbiota dysbiosis and metabolic disorder development; one of the potential mechanisms is the disruption of the lung–gut axis, leading to gut microbiota dysbiosis, intestinal dysfunction, systemic inflammation, and metabolic disease. Short-chain fatty acids (SCFAs) are the primary metabolites of gut bacteria, which are derived from the fermentation of dietary fibers. They activate G-protein-coupled receptor (GPCR) signaling, suppress histone deacetylase (HDAC) activity, and inhibit inflammation, facilitating the maintenance of gut health and biofunction. The aforementioned gut microbiota dysbiosis reduces SCFA levels. Treatment targeting SCFA/GPCR signaling may alleviate air pollution–associated inflammation and metabolic disorders, which involve lung–gut axis disruption.

Evaluating the Role of Glycemic Control in Modulating Pulmonary Function Among Smokers With Diabetes Mellitus: A Systematic Review

“…Data from the Danish National Registry suggests that those with type 2 diabetes are more likely to require antibiotics, with an increased likelihood observed before and after diabetes diagnosis [ 26 ]. Cheng et al [ 27 ] discuss how smoking and exposure to particulate matter can disrupt the gut microbiota and contribute to systemic inflammation and metabolic diseases, implicating the lung-gut axis in the progression of these disorders. They propose that targeting SCFA/GPCR signaling could help mitigate these effects, a novel approach not covered in our review.…”

Systematic Investigation of the Effect of Lactobacillus acidophilus TW01 on Potential Prevention of Particulate Matter (PM)2.5-Induced Damage Using a Novel In Vitro Platform

“…PM-mediated microbiota dysbiosis and metabolic disorder may be due to lung-gut axis disruption [13], as PM upregulates lung oxidative stress, systemic Foods 2023, 12, 3278 2 of 13 inflammation, gut barrier dysfunction, and microbiota dysbiosis [14]. Inflammatory lung diseases (such as asthma, pulmonary emphysema, and even lung cancer) [5,15] are associated with microbiota dysbiosis mediated by PM [16], resulting in impaired gut barrier function and reduced serum lipopolysaccharide (LPS) levels [17].…”