The Role of the Gut–Liver Axis in the Development of Liver Diseases Induced by Selected Environmental Pollutants: A Narrative Review

Abstract

Environmental pollution has emerged as a critical global health threat, with xenobiotic exposure increasingly linked to the pathogenesis of chronic liver diseases. The gut–liver axis has been proposed as a potential mediator in the body’s response to these insults. This review evaluates how selected environmental pollutants—heavy metals, particulate matter (PM), and endocrine-disrupting chemicals (EDCs), particularly Bisphenol A (BPA)—disrupt this homeostatic balance. Evidence indicates that environmental toxins induce gut dysbiosis and impair intestinal barrier integrity. This “leaky gut” phenomenon facilitates the translocation of endotoxins (LPS) into the portal circulation, where they trigger the TLR4/NF-κB signaling pathway in the liver. This leads to the activation of chronic inflammation, oxidative stress, and significant lipid accumulation in the liver. Furthermore, EDCs interfere with hepatic nuclear receptors, directly deregulating lipid metabolism and driving the progression of metabolic dysfunction-associated steatotic liver disease (MASLD). By highlighting the gut–liver axis as a key pathway affected by selected environmental contaminants, this review provides a mechanistic foundation to guide future research toward targeted preventive and therapeutic strategies.