ORIGINAL ABSTRACT

Glyphosate (GLY) is an herbicide used for rural and urban weed control. Urinary GLY in women is associated with shortened gestational length yet effects of GLY on offspring due to maternal exposure are unclear. This study tested the hypothesis that maternal chronic pre-conceptional GLY exposure would cause phenotypic and molecular changes in F1 offspring. Female C57BL/6 mice (7-week-old; n = 40) received saline vehicle control (CT; n = 20) or GLY (2 mg/kg; n = 20) daily per os for 10 weeks. At dosing completion, females were housed with unexposed males and divided into Cohort 1 who were euthanized at gestation day 14 (n = 10 per treatment) and Cohort 2 who completed gestation (n = 10 per treatment). F1 female ovarian and liver samples underwent LC-MS/MS and bioinformatic analysis. Maternal exposure did not affect litter (P > .05) sex ratio, or embryonic or neonatal gross phenotypes. In Cohort 2 offspring, no treatment effect on (P > .05) offspring anogenital distance, puberty onset, or ovarian follicular composition was noted. Body weight was increased (P < .05) in male GLY-exposed compared with CT dam offspring. F1 females from GLY-exposed dams had altered (P < .05) abundance of 54 ovarian and 110 hepatic proteins. Pathways altered in the ovary (false discovery rate [FDR] ≤ 0.07) included thermogenesis and phosphatidylinositol-3 kinase-AKT signaling and in liver (FDR ≤ 0.08) included metabolic, glutathione metabolism, oxidative phosphorylation, non-alcoholic fatty liver disease, and thermogenesis. Thus, pre-conceptional GLY exposure affected offspring phenotypic and molecular profiles potentially impacting reproductive health.