Flaxseed protein-derived sulfhydryl peptides mitigate cardiac damage induced by lead exposure through lead chelation and modulation of gut microbiota

Lead exposure causes multi-organ damage. Previous research has shown that flaxseed protein-derived sulfhydryl peptides (FPSPs) mitigate lead-exposed liver and kidney damage. However, the impact of FPSPs on cardiac damage remains unclear. This study evaluated the chelating ability of FPSPs on Pb 2+ and their physiological efficacy in reducing cardiac damage in lead-exposed rats through molecular dynamics simulations and multi-omics. The results indicated that FPSPs chelate Pb 2+ via sulfhydryl, carboxyl, hydroxyl, and amino groups. FPSPs supplementation decreased cardiac lead content by 81.30%, enhanced fecal lead excretion by 1.675-fold, and attenuated cardiac oxidative stress and inflammatory. FPSPs consumption increased the abundance of beneficial gut bacteria and SCFAs levels. In summary, FPSPs mitigate lead-exposed cardiac damage through dual pathways: (i) chelating Pb 2+ to promote its excretion and reduce cardiac lead accumulation; (ii) modulating the gut microbiota to increase SCFAs, alleviating cardiac oxidative stress and inflammation.