Glyphosate and Glyphosate-based herbicide exposure during the peripartum period affects maternal brain plasticity, maternal behavior and microbiome.
J Neuroendocrinol. 2019 May 7:e12731. Epub 2019 May 7. PMID: 31066122
Glyphosate is found in a large array of non-selective herbicides such as Roundupand is by far the most widely used herbicide. Recent work in rodent models suggests that Glyphosate-based herbicides during development can affect neuronal communication and result in altered behaviors, albeit through undefined mechanisms of action. To our knowledge, no study has investigated the effects Glyphosate or its formulation in herbicide on maternal behavior and physiology. Here, relatively low doses of Glyphosate (5 mg/kg/d), Roundup(5 mg/kg/day of Glyphosate equivalent), or vehicle were administered by ingestion to Sprague Dawley rats from gestational day (GD) 10 to postpartum day (PD) 22. The treatments significantly altered licking behavior toward pups between PD2 and PD6. We also show in the dams at PD22, Roundup exposure affected the maturation of doublecortin-immunoreactive new neurons in the dorsal dentate gyrus of the hippocampus of the mother. In addition, the expression of synaptophysin, was upregulated by glyphosate in the dorsal and ventral dentate gyrus and CA3 regions of the hippocampus, and downregulated in the cingulate gyrus. While a direct effect of glyphosate alone or its formulation on the central nervous system is currently not clear, we show here that gut microbiota is significantly altered by the exposure to the pesticides, with significant alteration of the phyla Bacteroidetes and Firmicutes. This is the first study to provide evidence that glyphosate alone or in formulation (Roundup) differentially affects maternal behavior and modulates neuroplasticity and gut microbiota in the mother. This article is protected by copyright. All rights reserved.