ORIGINAL ABSTRACT

Glyphosate, the active ingredient in herbicide Roundup, is the most widely used environmental contaminant that has been extensively studied for its potential carcinogenic effects. In the US alone, a staggering 81% of the US population ≥6 years of age is exposed to glyphosate. Notably, this coincides with the alarming rise in the incidence of hypertension, the single largest risk factor for global mortality through cardiovascular diseases. Here we asked if there is a link between glyphosate exposure and hypertension, the premise being that glyphosate targets the shikimate pathway present in gut microbiota coupled with more recent knowledge that gut microbiota causally regulate blood pressure. We hypothesized that glyphosate elevates hypertension through microbiota-mediated mechanisms and document a highly concerning detrimental effect of glyphosate by demonstrating a causal link between oral glyphosate exposure and significant elevation in blood pressure. Gut microbiota was identified as the central mediator of this effect. Mechanistically, glyphosate-mediated elevation in blood pressure was through disruption of both gut-liver and gut-vascular homeostasis via FXR-signaling and accumulation of the microbial metabolite shikimic acid, respectively. Together, these findings underscore the need to reconsider the unabated use of this herbicide, which adversely affects a cardinal sign of health.