Nrf2/HO-1 Dysregulation is Involved in the Microplastic-Induced Gut–Liver Axis Damage Mechanism and the Protective Effect of Astaxanthin

As one of the most consumed meat products globally, microplastics (MPs) residues in chickens may enter the human body through the food chain. Therefore, this study aimed to investigate the adverse effects of MPs exposure on chicken health and the detoxification mechanisms of astaxanthin (AST). We found that MPs significantly impaired liver function, inducing injury characterized by hepatocyte ferroptosis, inflammation, lipid disorder, and fibrosis. This hepatic damage was linked to MPs-induced gut microbiota dysbiosis and disruption of the intestinal barrier. AST exerted hepatoprotective effects by activating the Nrf2/HO-1 signaling pathway and attenuating hepatic oxidative stress and ferroptosis. In parallel, AST improved gut microbiota composition and intestinal barrier integrity, thereby potentially reducing gut-derived inflammatory burden. Together, these findings suggest that AST confers liver protection through both direct hepatic actions and indirect modulation of the gut-liver axis.