MeP Induces Metabolic Disorder and Liver Damage at Human-Relevant Exposure Levels: Role of the Gut Microbiota.

Methylparaben (MeP) is a widely used preservative found in many consumer products that leads to extensive human exposure. Despite some health concerns, our understanding of MeP's effects on metabolic homeostasis remains limited. This study investigated the effects of MeP on body growth, metabolic homeostasis, and liver health in male C57BL/6J mice. We found that at human-relevant exposure levels, MeP impaired body weight gain, elevated serum tumor necrosis factor-α (TNF-α), disrupted metabolic parameters, and caused liver injury. In addition, these toxic effects were associated with altered gut microbiota composition. Depleting gut bacteria with antibiotics abolished MeP-induced adverse effects on weight, inflammation, and metabolism, although liver damage persisted. This study provides important insights into MeP toxicity in metabolic homeostasis and highlights the key regulatory roles of the gut microbiota.