The effect of maternal exposure to herbicide, glufosinate ammonium on synapse formation in offspring’s brain
The research group of Drs. Izumi, Yoshida, and colleagues (Department of Molecular Neuroscience, Faculty of Medicine, and Research Center for Idling Brain Science, University of Toyama) has discovered developmental synapse pathology caused by herbicide glufosinate ammonium (GLA) exposure during pregnancy in a mouse model.
Epidemiological studies have suggested that exposure to environmental factors such as infection, nutrition and exposure to chemicals during pregnancy contribute to neurodevelopmental disorders. Through numerous experiments with pesticide exposure, data have accumulated regarding primary changes within neuronal cells, and eventual adverse outcomes such as learning and behavioral abnormalities. However, the pathogenic mechanism linking primary cellular-level changes to the final phenotypes of individual animals remains elusive.
In the present study, we revealed that GLA exposure during pregnancy disrupts presynaptic differentiation in cultured neurons from embryos, and this disruption is not induced by subchronic direct administration of GLA to cultured neurons. We also found a slight delay in parvalbumin-positive neuronal development after birth due to maternal GLA exposure during pregnancy.
Thus, we propose that GLA exposure during pregnancy can affect the maternal environment, which in turn exerts an indirect effect on the fetal brain resulting in neurodevelopmental delay with partial impairment in synapse formation.
This is the first demonstration that pesticide exposure during pregnancy affects the ability of synapse formation in offspring. Recent studies suggest a similar causal relationship between viral infections or hypertension during pregnancy and neurodevelopmental disorders in children. Therefore, these maternal environmental changes may have a common pathogenic mechanism. Further investigation into the molecular basis of developmental synapse pathology due to maternal environmental changes is expected to identify molecular mediators between mother and fetus, which will contribute to the development of prevention and treatment for neurodevelopmental disorders.
Original article information
Frontiers in Molecular Neuroscience
Developmental synapse pathology triggered by maternal exposure to the herbicide glufosinate ammonium
Hironori Izumi, Maina Demura, Ayako Imai, Ryohei Ogawa, Mamoru Fukuchi, Taisaku Okubo, Toshihide Tabata, Hisashi Mori, Tomoyuki Yoshida