Exposure to Grilled Lamb‐Borne Carbon Quantum Dots Induces Intrahepatic Cholestasis by Activating the Intestinal Microbial‐Derived Lipopolysaccharide‐TLR4 Pathway

Why It Matters

The findings reveal a previously unrecognized hepatotoxic risk of food‑borne nanomaterials, suggesting that common grilling practices could contribute to liver disease. Understanding this pathway enables targeted dietary interventions and regulatory scrutiny of nanoscale food contaminants.

Key Takeaways

• Grilled lamb CQDs cause liver and gut barrier damage.
• CQDs increase intestinal LPS, activating TLR4‑MyD88 pathway.
• Upregulated bile acid synthesis genes lead to intrahepatic cholestasis.
• Bile acid excretion transporters Bsep and Mrp2 are downregulated.
• Probiotic Lactiplantibacillus plantarum reverses cholestasis via microbiome modulation.

Pulse Analysis

The rise of nanotechnology in food processing has introduced carbon quantum dots (CQDs) as unintended by‑products of high‑temperature cooking. These nanoscale particles possess abundant surface functional groups that facilitate organ accumulation, raising concerns about chronic exposure through everyday diets. Recent animal studies underscore that even modest doses of grilled‑lamb‑derived CQDs can breach intestinal defenses, setting the stage for systemic toxicity that extends beyond traditional food contaminants.

At the molecular level, CQDs act as a catalyst for gut‑derived lipopolysaccharide (LPS) release, which engages the Toll‑like receptor 4 (TLR4)‑MyD88 axis in both the intestine and liver. This signaling cascade amplifies NF‑κB activity, driving overexpression of bile‑acid synthesis enzymes such as Cyp7a1, Cyp8b1, and Cyp27a1 while simultaneously repressing key export pumps Bsep and Mrp2. The resulting bile‑acid pool becomes skewed toward FXR antagonists like tauro‑β‑muricholic acid, exacerbating intrahepatic cholestasis and highlighting a novel link between dietary nanomaterials and liver dysfunction.

The translational relevance is immediate: probiotic intervention with Lactiplantibacillus plantarum restored microbial balance, reduced LPS burden, and re‑established barrier integrity, effectively reversing cholestatic markers. These insights prompt a reevaluation of food safety standards for nanomaterial residues and encourage the development of dietary strategies that incorporate targeted probiotics. As the food industry continues to adopt high‑heat techniques, integrating nanotoxicology into risk assessments will be essential to safeguard public health.