Microplastics harm the gut lining and may cause brain inflammation by disrupting gut-brain communication through key cell signaling pathways

Exposure to 10 and 100 mg/kg BW of polyethylene and polypropylene microplastics for 45 days significantly disrupted intestinal barrier integrity.

• Intestinal barrier integrity was compromised, evidenced by reduced expression of zonula occludens-1.
• Exposure led to altered short-chain fatty acid profiles, indicating impaired gut microbial activity.
• Increased oxidative stress was observed, marked by reduced antioxidant defense and heightened lipid peroxidation.
• Elevated inflammatory mediators and altered neurochemical markers were detected in both small intestine and brain tissues.
• Behavioral abnormalities and histopathological changes were noted, suggesting neuroinflammatory toxicity linked to gut-brain axis dysregulation.
• Polyethylene microplastics caused more severe toxic effects compared to polypropylene microplastics, especially at the higher dose.

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