Polychlorinated Biphenyls and Nonalcoholic Fatty Liver Disease

Polychlorinated biphenyls (PCBs) have been associated with abnormal liver enzymes and suspected nonalcoholic fatty liver disease (NAFLD) in cohort studies. NAFLD affects greater than 25% of the global population and may result in liver-related mortality. Both dioxin-like and nondioxin-like PCBs have been associated with NAFLD, but their effects and mechanisms differ. Dioxin-like PCBs altered the gut–liver axis and microbiome and caused hepatic steatosis by disrupting hepatic lipid metabolism. In contrast, nondioxin-like PCBs reduced the liver's protective responses to promote diet-induced NAFLD. Mechanisms included the disruption of phosphoprotein signaling resulting in altered nuclear receptor function.