Development of a gut microbe-targeted non-lethal therapeutic to inhibit thrombosis potential without enhanced bleeding

Trimethylamine-N-oxide (TMAO), a microbiota-dependent metabolite derived from trimethylamine (TMA)-containing nutrients abundant in a Western diet, enhances both platelet responsiveness and in vivo thrombosis potential and predicts incident atherothrombotic event risks in clinical studies. Utilizing a mechanism-based inhibitor approach targeting a major microbial TMA-generating enzyme (CutC/D), we developed potent, time-dependent and irreversible inhibitors that do not affect commensal viability. In animal models, a single oral dose significantly reduced plasma TMAO levels for up to 3 days with limited systemic exposure in the host. This was achieved by the selective accumulation of inhibitor within intestinal microbes to millimolar levels, a concentration over a million-fold higher than needed for therapeutic effect. In animal models, inhibition of microbial TMA/TMAO generation rescued diet-induced enhanced platelet responsiveness and thrombus formation, without observable toxicity or increased bleeding risk. The present studies reveal mechanism-based inhibition of gut microbial TMA/TMAO production reduces thrombosis potential, a critical adverse complication in heart disease. They also offer a generalizable approach for the selective non-lethal targeting of gut microbial enzymes linked to host disease, while limiting inhibitor systemic exposure in the host