Journal of agricultural and food chemistryJan 28, 2026

Long-Term Eating of Heat-Processed Food Polymers Speeds Brain Inflammation in Alzheimer’s Mice Through the Gut Microbe-Brain Link

Gut-Brain Axis Weekly Brief ↗PubMed ↗DOI ↗

Updated Jun 27, 2026

Abstract

Essence

Carbon polymers isolated from roasted lamb accelerated gut-driven inflammation and neuroinflammatory changes in Alzheimer disease model mice.

Evidence

This preclinical mouse study exposed transgenic APPswe/PSEN 1dE9 mice to processed food-derived carbon polymers and measured gut dysbiosis, endotoxin and tryptophan changes, intestinal and systemic inflammation, blood-brain barrier permeability, neuroinflammation, and synaptic dysfunction.

Caveat

The results come from isolated dietary polymers and a transgenic mouse model, so they do not establish the human risk of processed-food carbon polymers.

Simplified

Processed foods are increasingly associated with the prevalence of neurodegenerative diseases, including Alzheimer disease (AD). Therefore, it is essential to elucidate the underlying mechanisms by which these processed foods influence AD. This study identified and isolated an emerging dietary risk factor, carbon-based polymers (CPs), from processed foods, specifically roasted lamb. Further investigation revealed that prolonged exposure to CPs induced gut microbiota dysbiosis along with elevated endotoxin production and perturbed tryptophan metabolism, thereby leading to intestinal inflammation. These alterations facilitated the entry of LPS into the blood circulation, which subsequently triggered systemic inflammation and increased the blood-brain barrier permeability. Ultimately, they accelerated neuroinflammation and synaptic dysfunction in transgenic APPswe/PSEN 1dE9 mice via the LPS-TLR4-NF-κB signaling pathway. Collectively, this study advances our understanding of CPs as potential accelerators of neuroinflammation, providing a scientific basis for reevaluating the biosafety of dietary CPs in humans, especially for at-risk populations.