Arabinoxylan and glycolysis inhibitors alleviate trimethylamine accumulation and gut barrier impairment by inhibiting the PERK pathway

Abstract

As a global driver of cardiovascular disease, atherosclerosis is linked to the accumulation of trimethylamine (TMA), a metabolite produced when gut microbiota metabolize dietary choline. However, current strategies targeting TMA remain ineffective, largely due to poorly understood interactions involving the gut-mucosal barrier. To address this knowledge gap, we evaluated these interactions in the context of TMA accumulation using a murine model. Specifically, we integrated 16S rRNA sequencing, metabolomics, transcriptomics, and proteomics analyses to investigate the chemical processes and key targets underlying the intestinal effects of choline-rich diets and their inducers, combined with nutritional intervention strategies. The findings revealed that excessive choline intake activated the PERK signaling pathway, upregulated the expression of Trim40 and TMA transporters (Slc family), downregulated the expression of tight junction proteins (Tjp1/2/3, Ocln), and induced histopathological damage to the gut barrier. Additionally, choline-rich diets caused gut microbiota dysbiosis, elevated serum TMA levels, and increased lipopolysaccharide (LPS) accumulation in intestinal contents. Arabinoxylan (AX) treatment mitigated these adverse effects by restoring gut microbiota balance and gut barrier integrity (via regulating Tjp1/2/3, Ocln expression and downregulating Trim40), suppressing PERK pathway genes (14.1%-60.6% reduction), and lowering TMA levels. Notably, co-treatment with AX and glycolysis inhibitors (particularly the pyruvate kinase inhibitor) exerted a synergistic effect, further reducing TMA levels and Trim40 expression. We identified a PERK-TMA axis as a key player in the pathophysiology of gut barrier impairment. In this axis, glycolysis inhibitors enhanced AX-mediated restoration of the PERK pathway, with reductions in PERK-related gene expression ranging from 1.11% to 67.4% compared to the AX monotherapy group. These results characterize a regulatory chain, "metabolic stress reduction, TMA transporter inhibition, barrier recovery", which exhibits potential for reducing TMA accumulation.