Glyphosate affects the neurochemical phenotype of the intramural neurons in the duodenum in the pig

Abstract Background Glyphosate‐based herbicides have been one of the most intensively used pollutants worldwide and food products containing glyphosate are an essential component of human and animal diet. The aim of present study was to determine the effect of glyphosate intoxication on the neurochemical properties of the enteric nervous system (ENS) neurons located in the wall of the porcine duodenum. Methods Fifteen sexually immature gilts divided into 3 groups were used: control—animals receiving empty gelatin capsules; G1—animals receiving a low dose of glyphosate—corresponding to the theoretical maximum daily intake (TMDI) ‐ 0.05 mg/kg bw/day; G2—animals receiving a higher dose of glyphosate—corresponding to the acceptable daily intake (ADI)—0.5 mg/kg/day in gelatin capsules orally for 28 days. After this time, the animals were euthanized and small intestine samples were collected. Frozen sections were then subjected to the procedure of double immunofluorescent staining. Key results Glyphosate supplementation led to alterations in the neurochemical code of the ENS neurons in the porcine duodenum. Generally, increased population of neurons immunoreactive to PACAP, CGRP, CART, nNOS, and a decreased number of VAChT‐like immunoreactive neurons were noted. Conclusions and inferences It may be a first preclinical symptom of digestive tract dysfunction in the course of glyphosate intoxication and further studies are needed to assess the toxicity and risks of glyphosate to humans.