Prenatal glyphosate exposure disrupts the gut-brain axis across several generations in mice.
Glyphosate, a widely used herbicide in North America, has become prevalent in the food supply, raising concerns about potential health impacts. In this exploratory study, male and female F0 mice were exposed to glyphosate through drinking water during mating and gestation. We investigated whether prenatal exposure at dietary-relevant levels (0.01 mg/kg/day, Average American Diet, [AAD]) or the U.S. EPAs acceptable daily intake (1.75 mg/kg/day, [EPA upper limit]) altered gut, metabolic, and behavioral outcomes across two generations in mice with or without genetic susceptibility to colitis (Muc2+/- and Muc2-/-, respectively). Healthy (Muc2+/-) offspring of glyphosate-exposed mice exhibited colonic goblet cell depletion, reduced mucin-2 expression, and pro-inflammatory cytokine profiles in both F1 and F2 generations. These healthy (Muc2+/-) offspring also developed metabolic dysfunction, including impaired glucose tolerance, insulin resistance, and reduced GLP-1 in serum. Behavioral deficits were also observed in healthy (Muc+/-) mice including reduced locomotion and working memory, and these changes were associated with altered microbiome composition and gut-brain mediators. These findings suggest that prenatal glyphosate exposure, even below regulatory thresholds, may disrupt multiple physiological systems across generations, highlighting the need for further research and regulatory consideration.