High l-Carnitine Ingestion Impairs Liver Function by Disordering Gut Bacteria Composition in Mice

Area of Science:

• Microbiology
• Toxicology
• Metabolomics

Background:

• L-carnitine is essential for energy metabolism.
• High-dose L-carnitine's impact on gut microbiota and liver health requires further investigation.

Purpose of the Study:

• To investigate the effects of high L-carnitine consumption on mouse intestinal microbiota, liver function, and metabolite profiles.
• To explore the correlation between specific gut bacteria and liver injury markers.

Main Methods:

• Mice were supplemented with high doses of L-carnitine.
• 16S rRNA sequencing was used to analyze gut microbiota composition.
• Liver function markers (AST, ALT), inflammatory cytokines, lipid metabolism, and antioxidant capacity were assessed.
• Correlation analysis was performed between microbial abundance and physiological parameters.

Main Results:

• High L-carnitine intake altered gut microbiota, increasing Anaerobiospirillum, Coriobacteriaceae, Akkermansia_muciniphila, and Helicobacter.
• Significant liver injury was observed, indicated by elevated AST/ALT, inflammatory cytokines (IL-1, IL-6, TNF-α, TNF-β), disordered lipid metabolism, and reduced antioxidant capacity.
• Anaerobiospirillum, Akkermansia_muciniphila, and Helicobacter were strongly correlated with liver injury markers (AST, IL-1, TNF-α, TNF-β, MDA).

Conclusions:

• High L-carnitine consumption can induce liver dysfunction through gut dysbiosis.
• The gut microbiota alterations are linked to increased TMAO metabolism and liver damage markers.