Isoliquiritin counteracts cadmium-induced intestinal damage in mice through enhancing intestinal barrier function and inhibiting apoptosis

Cadmium (Cd), a crucial toxic environmental pollutant, can induce damage to many organs, especially the gastrointestinal tract. Isoliquiritin (ISO), a critical flavonoid glycoside compound isolated from Glycyrrhiza uralensis, has anti-inflammatory, anticancer, antioxidant and other pharmaceutical value. However, the potential roles of ISO in Cd-induced intestinal damage have not been reported yet. This study aimed to research the beneficial effects of ISO on Cd-induced intestinal damage and identify its underlying mechanisms. Our results showed that ISO reduced inflammation by suppressing the production of pro-inflammatory cytokines and the activity of serum Lipopolysaccharide (LPS) in mice with Cd exposure. In terms of mechanism, ISO administration protected the intestinal barrier function through increasing the expression of tight junction proteins and Muc2. Furthermore, ISO could significantly suppress Cd-induced intestinal apoptosis and activation of NLRP3 inflammasome. Interestingly, inhibiting the activation of NLRP3 by nigericin completely blocking the effect of ISO on apoptosis. Most importantly, ISO markedly abrogated Cd-induced cell damage and NLRP3 inflammasome activation in vitro. Taken together, these findings suggest that ISO reduces Cd-induced intestinal damage by increasing the goblet cells, improving intestinal barrier, suppressing NLRP3 inflammasome activation and inhibiting apoptosis, which may offer a novel strategy against the toxic effects of heavy metals.